A blog for the friends of Avalonia Land Conservancy, acquiring and protecting natural habitats in southeastern Connecticut

Monday, March 30, 2015

Word of the Season

By Beth Sullivan

Phenology…a
word I have heard on multiple occasions in the last week! A word I
pretty much knew the definition of, or the idea of, even more or less
wrote about a few weeks back. But I decided to look it up to double
check why it seemed to be a buzz word recently.

Phenology-noun: The
science dealing with the influence of climate on the recurrence of
such annual phenomena of animal and plant life such as budding and
bird migrations.

We await the first Osprey in Mid-March.

Those of us who are
nature watchers know the concept well, even let the word flow off our
tongues frequently. We have kept journals and logs over years and
decades, marking the cycle of seasons and annual “firsts”
(Thoreau, Leopold and Teale did too). Over the last years of writing
this blog, I have noted first occurrences of some of my favorites:
“Return of the Osprey,” “The First Tree Swallow,” “First
Purple Martins to return to Their Gourd Houses.” We wait for the
Skunk cabbage to show itself from beneath the snow. We wait for the
first warm rainy night when the salamanders and wood frogs leave
their wintering spots and move to vernal ponds for egg laying. We
eagerly listen for the first spring Peepers. I wait for the chipmunk
in my stone wall.

Spring Peepers wait for the ice to melt and will call on warmer nights

It's not just the
length of day

Many of these events
are regulated by day length. Birds usually begin their Northward
migration based on the length of the day, not necessarily the
temperature. They do not know what the conditions are up North.
Amphibians, deep in the ground, are stirred by temperature. Warming
air temperatures translate to warming soil, and melting ice and
stimulates them to move. The warming of the soil also dictates
plant growth from seeds or dormant roots. Air temps as well as day
light will determine tree budding and sap flow.

Populations of Canada Geese head north based on day length

This year we are all
feeling a bit askew…whether or not we realize, it is phenology at
work! The very cold, very late spring has everything off kilter.
Ice is not off the waterways, and returning osprey need to fish.
Overwintering water fowl are starving as the ice covers the shallow
water, and they cannot graze on plants on the bottom. Sap flows are
late, most insects are not emerging yet, and birds returning will not
find food. We all know the Robins can’t find their March worms yet!
If insects do emerge with the warmth, the blossoms are not yet
present for them to feed on. Will the pollinators they need be out
of sync when the flowers do open?

Persistent ice has starved many dabbling ducks

Those spring ephemeral
wildflowers that should be well up by now are still dormant. Will
their season be cut short? Will they be able to set seed in time?
Will hibernating mammals respond to day length or warming before they
emerge, and will there be plants readily available as food sources if
the snow has not melted?

In warmer years, Blood Root could have been in bloom now

Think of how cold the
water of Long Island Sound has been. We know it will affect our
weather along the shore, but how will it affect the migration of fish
and horseshoe crabs?

Temperature matters too

It is a delicately
balanced web, and the seasonal cycles of temperature and light play a
critical part of the balance.

It's a lot to think
about. All we can do is continue to make our journal entries of our
observations and wait and see what comes next. That is Phenology!

My Chipmunk made an appearance while snow was covering the walls

This Spotted Salamander made his move on March 26

PS:
On 3/26 I saw my chipmunk! And the Spotted Salamanders and Wood
Frogs began their move!